Laws are meaningless if they are never enforced or are simply ignored. Which happens all the time in China.
It is not easy to fire people. Sure, in normal situations. But when appropriate, government is going to ignore all these and do whatever necessary, and maybe even threaten to put you or your family in jail. Want to go to court? Good luck, the judges are going to stand with the government.
Another example: the constitution says that Chinese people have the freedom to speak, publish and demonstrate etc. Tell me how that has worked out.